From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755867Ab1JSLRV (ORCPT ); Wed, 19 Oct 2011 07:17:21 -0400 Received: from moutng.kundenserver.de ([212.227.126.171]:49309 "EHLO moutng.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753558Ab1JSLRT (ORCPT ); Wed, 19 Oct 2011 07:17:19 -0400 Message-ID: <4E9EB1BC.9020709@yahoo.co.uk> Date: Wed, 19 Oct 2011 12:17:16 +0100 From: Sam Tygier User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.23) Gecko/20110922 Thunderbird/3.1.15 MIME-Version: 1.0 To: linux-kernel@vger.kernel.org Subject: 3.1rc10 null pointer dereference ideapad_backlight_notify_power Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Provags-ID: V02:K0:kIxA+AAUhlYM8Xfgzd+v2xTirdI5gwOwnZom0iqGQef xwWxZA7Kl3emZfp/L7xMl8++uUSWfhDEZHz1PrOw7S9KJ7O7QI Szm+9oOyHOnp/m9spCMS0iDbb4i/saG+puABwKdzRGnheGLghV 00jBuBb+ftdB/t4ihwbO3vqa01aN3EBH8ZdguZWOpxzstasFl5 EpxnjuaouSWsXJQQRilMWqFd/75tK13CiM67Sr65r51nLgpIl6 +zXrv1uarDmKyJXRo2G5ii9TCmRTQgVHsAXxNbDTcNbJFCD85Z EtfqHzf0m9HdbISiVqdqqOQ0SJ5ogw0B2uZr/D7m+4MKgnuBg= = Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In kernels 3.1rc9 and 3.1rc10 (from the ubuntu mainline repo) I get a crash when disabling and then enabling the screen backlight with the alt+f2 key on a lenovo ideapad S12 (intel version). The crash does not occur with 3.0 kernels in ubuntu. I have not tested earlier 3.1 rcs. The crash message scrolls to fast to see, it is not writen to a log, and i dont see it on a USB serial console (I may be doing something wrong, but I do see other messages during boot). I managed to get some photos of the message. interesting parts are: BUG: unable to handle kernel NULL pointer dereference at 00000008 IP: [] ideapad_backlight_notify_power+0x2e/0x40 [ideapad_laptop] *pde = 00000000 Oops: 0002 [#1] SMP call trace functions: ideapad_acpi_notify acpi_device_notify acpi_ev_notify_dispach acpi_os_execute_deferred process_one_work ? acpi_os_wait_events_complete ????????? can't read this one kthread kthread_bind kernel_thread_helper i put the photos at http://www.hep.manchester.ac.uk/u/sam/pub/ideapad/ if it would be helpfull, i could try a few more times for sharper photos. please let me know if there is any other useful information you need. thanks, sam